使用 FreeType 2 字体将文本写入图像

说明

array imagefttext ( resource $image , float $size , float $angle , int $x , int $y , int $color , string $fontfile , string $text [, array $extrainfo ] )

参数

image

由图象创建函数(例如 imagecreatetruecolor())返回的图象资源。

size

The font size to use in points.

angle

The angle in degrees, with 0 degrees being left-to-right reading text. Higher values represent a counter-clockwise rotation. For example, a value of 90 would result in bottom-to-top reading text.

x

The coordinates given by x and y will define the basepoint of the first character (roughly the lower-left corner of the character). This is different from the imagestring(), where x and y define the upper-left corner of the first character. For example, "top left" is 0, 0.

y

The y-ordinate. This sets the position of the fonts baseline, not the very bottom of the character.

color

The index of the desired color for the text, see imagecolorexact().

fontfile

The path to the TrueType font you wish to use.

Depending on which version of the GD library PHP is using, when fontfile does not begin with a leading / then .ttf will be appended to the filename and the library will attempt to search for that filename along a library-defined font path.

When using versions of the GD library lower than 2.0.18, a space character, rather than a semicolon, was used as the 'path separator' for different font files. Unintentional use of this feature will result in the warning message: Warning: Could not find/open font. For these affected versions, the only solution is moving the font to a path which does not contain spaces.

In many cases where a font resides in the same directory as the script using it the following trick will alleviate any include problems.


<?php
// Set the enviroment variable for GD
putenv('GDFONTPATH=' . realpath('.'));

// Name the font to be used (note the lack of the .ttf extension)
$font = 'SomeFont';
?>

text

Text to be inserted into image.

extrainfo

Possible array indexes for *`extrainfo`*
Key	Type	Meaning
linespacing	float	Defines drawing linespacing

返回值

This function returns an array defining the four points of the box, starting in the lower left and moving counter-clockwise:

0	lower left x-coordinate
1	lower left y-coordinate
2	lower right x-coordinate
3	lower right y-coordinate
4	upper right x-coordinate
5	upper right y-coordinate
6	upper left x-coordinate
7	upper left y-coordinate

范例

Example #1 imagefttext() example


<?php
// Create a 300x100 image
$im = imagecreatetruecolor(300, 100);
$red = imagecolorallocate($im, 0xFF, 0x00, 0x00);
$black = imagecolorallocate($im, 0x00, 0x00, 0x00);

// Make the background red
imagefilledrectangle($im, 0, 0, 299, 99, $red);

// Path to our ttf font file
$font_file = './arial.ttf';

// Draw the text 'PHP Manual' using font size 13
imagefttext($im, 13, 0, 105, 55, $black, $font_file, 'PHP Manual');

// Output image to the browser
header('Content-Type: image/png');

imagepng($im);
imagedestroy($im);
?>

注释

Note: 此函数需要 GD 2.0.1 或更高版本(推荐 2.0.28 及更高版本)。

Note: 此函数仅在 PHP 编译时加入 freetype 支持时有效（--with-freetype-dir=DIR ）。

更新日志

版本	说明
4.3.5	`extrainfo` was made optional.